Which mode of inheritance produces heterozygotes with phenotypes that differ from either homozygote but typically more closely resembles one homozygous phenotype than the other?"
A) complete dominance
B) incomplete dominance
C) codominance
D) epistasis
E) incomplete penetrance
Answer:
B) incomplete dominance
Explanation:
Incomplete dominance occurs when the dominant allele of a gene is not able to mask the expression of the recessive allele completely. This results in the expression of a phenotype in the heterozygous genotypes that differ from both homozygous genotypes. However, the phenotype of the heterozygote is closer to one of the homozygous genotypes.
For example, the petal color in four o'clock plant is controlled by a gene with two alleles R and r. Here, the "R" allele can not produce enough pigment in heterozygous conditions to completely mask the expression of the "r" allele and the phenotype of the "Rr" plant is "pink". On the other hand, the phenotype of "RR" plant is red while that of the "rr" plant is "white".
Answer:
Neurotransmitters are released from axon terminals via exocytosis
Explanation:
Dendrite is the receiving part of the presynaptic neuron, while axon is the transmitting part of the neuron. So, after initiation, action potentials travel down axons to the terminals. Action potential travels through the membrane of the presynaptic cell causing the voltage-gated channels permeable to calcium ions to open. Ca2+ flow through the presynaptic membrane and increase the Ca concentration in the cell which will activate proteins attached to vesicles that contain a neurotransmitter (e.g. acetylcholine). Vesicles fuse with the membrane of the presynaptic cell, thereby release their contents into the synaptic cleft-space between the membranes of the pre- and postsynaptic cells (exocytosis of the vesicle's content). Neurotransmitter ACh (from the vesicles) binds to its receptors on the postsynaptic membrane and its binding causes depolarization of the target cell (muscle cell). Depolarization occurs because sodium enters the cell as a result of neurotransmitter receptor binding.
<span>If an orange powder coating the bottom of rivers from water runoff through old coal mines is called acid mine drainage. Acid mine drainage is an outflow of acid water that came from coal mine areas or some metal mine areas.</span>
Answer:
High blood pressure is called hypertension or often referred to as the silent killer as it shows no symptoms at all.
Hope that helps!
